ehhhhhhhhmmmmmmmnnnnnnggg i dunno. honestly i dont think print will die. aside from the classique nerd who loves to collect their titles, theres something personally very satisfying about Having the comic. its similar to CDs, which still get shifted almost two decades since the MP3. also, publishing houses have the power to print work, and as comics mature as an art form and begin to be taken more seriously, we'll be less and less limited in publisher choices imo.
similarly, i dont think desktop reading will die. i read all my comics (print and web-) on desktop, and people arent gonna grow out of laptops. laptops are here to stay.
also i feel like theres not as much to do in mobile friendly format? i know you can get very experimental, if youve got the head for it, but i see my work here as practice for uni, and my future career, that could well be very print focused. regardless, uni will be looking at the tried and tested methods of comic artists of the print world. its not in my interest to make my comics scroll-to-reveal style, and its not in my interest either; its boring to me.
that all said, obviously it is a good idea to make your comic palatable on mobile. like you said, it can alienate a large chunk of your audience. but i think for a lot of people, making their comic in the style theyre enthusiastic about, which includes the paneling choices, is a priority over popularity. i think it would be nice if people did more with the scrolling, because its there and can be pretty useful, but if someone wants to print then what can they do?